The gun debate in the United States has intensified as shooting and killing
rampages have become an everyday American spectacle, and both sides of this
acrimonious debate have recently scored some points.

Gun-control advocates cheered when the Brady Bill became law. They are
now pressuring Congress to legislate new restrictions on firearm sales and
mandate background checks at gun shows. Escalating the battle, these activists
have also targeted the gun manufacturers through a series of lawsuits, much
the same way that the tobacco industry was challenged by smoking foes.

The pro-gun side has enjoyed its own victory, celebrating the adoption
of right-to-carry concealed handgun laws by more than 30 states, including
Georgia. These laws allow concealed handgun permits for any adult applicant
except convicted criminals and the mentally ill. Pro-gun groups argue that
concealed handguns have a deterrent effect, as criminals fearing an armed
response are less likely to commit crimes.

Gun-control advocates, on the other hand, have long maintained that gun
availability facilitates crime by increasing criminals' access to firearms.
Accidental shooting and juvenile abuse of guns are among other reasons,
they offer, for tightening gun laws. The gun-control campaign has benefited
from evidence supporting some of these arguments and the public outrage
over violence.

Recent mass shootings seem to have hurt the pro-gun agenda. The gun lobby
has a rather defensive role at the federal level, attempting to stop or
at least soften new gun-control initiatives. At the state level, however,
it is on the offensive: More than a dozen states have adopted concealed
handgun laws since 1992, and four states, including Georgia, have banned
cities from suing gun manufacturers. This disparity reflects cross-state
variations in attitude toward gun ownership and perhaps a higher marginal
efficiency of lobbying dollars at the state level. Both encourage the gun
lobby to target specific states.

Until recently, pro-gun groups have used the Second Amendment and anecdotal
evidence on the ineffectiveness of gun control laws to advance their cause.
The costs of a gun control legislation, they contend, are the individual
liberties it sacrifices, but the benefits are doubtful and perhaps none.
Recent work by economist and legal scholar John Lott has offered these groups
an offensive tool, offsetting the setbacks caused by the public outrage
over crime.

Lott's empirical results suggest that states which allow citizens to
carry concealed firearms experience a reduction in crime. His highly publicized
finding is the first non-anecdotal evidence that uses comprehensive data-covering
3,000 counties over 10 years-to link a permissive gun measure to the reduction
in crime. His 1998 book, More Guns, Less Crime: Understanding Crime and
Gun-Control Laws, and his 1997 article in the Journal of Legal Studies
extrapolate the concealed handgun finding to prescribe a civilian arms race
to battle crime. Lott's work has offered ammunition against gun control
laws and evidence to promote right-to-carry-gun state legislation.

Lott's finding has been promoted by program groups as scientific evidence
that links gun availability to reduced crime. The finding has also been
discussed on a wide range of media outlets, from radio and TV talk shows,
to CNN and CSPAN, from Time to George magazines, and in most
major newspapers. One reason for the media response is the finding runs
counter to conventional wisdom. Scholars, however, have pointed out several
technical flaws in Lott's work, but these criticisms, appearing as academic
squabble to nonexperts, have not received much publicity. Lott's questionable
work, meanwhile, is changing the pro-gun position from "more guns does
not lead to more crime" to "more guns leads to less crime."

Evidence against Lott's work, however, continues to grow. My work with
Emory economist Paul Rubin-described in "Lives Saved or Lives Lost:
The Effect of Concealed Handgun Laws on Crime," published in American
Economic Review in 1998-criticizes Lott on simple but fundamental grounds.
We show that Lott's work is erroneous not only in theory but also in its
arithmetic.

Lott's finding relies on the assumption that the effect of permissive
handgun laws on crime is identical across all counties and independent of
any county characteristics. This assumption is flatly contradicted by conventional
wisdom. Such laws would not have the same effect in crime-ridden urban areas
as they would in remote rural counties or affluent suburbs. Some of Lott's
results also assume that the number of arrests made by police does not depend
on the number of crimes committed! So rural counties with very few crimes
may presumably have more police arrests than urban counties with very large
crime rates.

Moreover, Lott's central results are invalid because of errors in computing
expected arrest rates: he obtains mostly negative numbers for arrests. For
example, more than 19,000 of approximately 33,000 county-level auto theft
arrests are "negative"; the number of negative arrest rates for
aggravated assault and property crimes are, respectively, 9,900 and 13,500.
What does a negative arrest rate mean? Obviously, the number of individuals
arrested for crimes can only be zero or positive.

Once we correct for these errors, the more-guns-less-crime claim disintegrates.
In fact, we show not only that Lott's strong crime-reducing effect does
not materialize, but also that concealed handguns lead to a higher robbery
rate.

The peer examination process usually exposes flawed research quickly.
The ideologically intoxicating finding of Lott-advocating a governmental
hands-off policy-seems to have impaired this healthy process. Endorsing
Lott's book, the arch-conservative Milton Friedman of the Hoover Institute
exults, "Lott has done us a service by his thorough, thoughtful, scholarly
approach to a highly controversial issue." Friedman, obviously, is
prepared to overlook all the documented inadequacies in Lott's work to embrace
his claim.

The academic survival of a flawed study may not be of much consequence.
But, unfortunately, the ill-effects of a bad policy, influenced by flawed
research, may hurt generations. It would be tragic for lawmakers to base
any gun laws on Professor Lott's More Guns, Less Crime claim.

Hashem Dezhbakhsh is interim co-chair and director of undergraduate
studies for the economics department.